Selecting mechanism.



iUNliTEU STATE@ Parana ricerca.

FRED R. MCMURRY, OF WESTWOOD, NEW JERSEY, ASSIGNOR, BY MESNE ASSIGNMENTS, TO WESTERN ELECTRIC COMAPANY, INCORPORATED, A CORPORATION OF NEW YORK.

SELECTING MECHANISM.

Application filed February 26, 1915.

To alliclzom z'z may concern Be it known t-hat l, Fano R. Mclvnnnv, a citizen ot the United States, residing at `Westwood. in the county of Bergen and State ot New Jersey, have invented certain new and useful Improvements in Selecting Mechanisms, of which the following is a full, clear, concise, and exact description.-

This invention relates to selecting mechanisms and one of its principal objects is to provide such a mechanism wherein the necessity for wiping contacts between insulated segmental structures and current collecting or distributing devices is obviated.

A further object is to provide a selecting mechanism employin a single elect-romechanical system whici may be used interchangeably as an impulse transmitter, receiver, or transmitter and receiver.

To the above ends, the invention contemplates the use of an electrically actuated switch controller, such as a cam or cams, so constructed and arranged that it afects the associated switches successivelyr to transmit a succession of current impulses or to distribute the effects of such impulses or to do both simultaneously.

The above and other objects of this invention will be fully set forth in the following description and claims, and will be more readily understood by reference to the accompanying drawing, in which- Figure 1 shows the apparatus and circuit connections in diagrammatic form; and Fig. 2 is a detail of one of the cams and its associatedswitch contact springs.

Thea switches 5, 6, 7, 8, 9, 15, 16, 17, 18 and 19 are insulatively secured to any desired form of support and may be considered as divided into two sets. One contact spring of each of the switches 5, 6, 7, S and 9, comprising one set, is connected to a front contact 20 of a relay 21. while the cooperating contact springs of the corresponding switches are grounded through the windings 25, 26, 27, 28 and 29 respectively of an electromechanism, such, for example, as the type selecting mechanism of a printing telegraph instrument. The other set is composed of switches 15, 16, 17 18 and 19 wh'ich have one of their contact springs connected to pole changers 35, 36, 37. 25H and Il!) respectively,-while the cooperating contact springs are connected to a fixed contact 45 of a line switch 16. Pole changers 35 to 39 inclusive,

Specification of Letters Patent.

Patented Jan. 16, 1917.

Serial No. 10,673.

by means of suitable circuit connections, are

current controlling means. may be selectively controlled by any suitable apparatus, asv for example, selecting keys arranged in the form of an ordinary typewriter keyboard. or in an automatic mechanism controlled by a perforated tape or the like.

The switches 5 to t) inclusive and 15 to 151 inclusive are operated by a plurality of cams 55 to ai) inclusive and G5 to ('39 inclusive mounted to rotate upon a cam shaft '70. These cams may be mounted separately, as shown, or as a unitary structure` and each may be provided with projections, such as the teeth 75 shown in Fig. 2. These teeth are adapted to engage one ot' the contact springs ot the corresl'ionding switch and are so positioned with respect to those on the other cams that the switches are successively actuated in pairs as the shaft 7() rotates. Thus, switches 5 and 15 are operated simultaneously, next switches and 16, and so on until the last pair 9 and 1f) are closed and then opened` completing one cycle of operations in the particular system disclosed. It is, however, to be understood that the numher of switches and the number and grouping otl the sets thereof may be altered without departing from the spirit of the invention.

ln the particular mechanism disclosed, each cam is provided with three teeth 75, which means that only one-third of a revolution is necessary for each cycle. This, however', ot course may be changed to suit any condition.' Shaft 70 is provided with suitable bearings and a ratchet wheel 7 6 having a suiiicient- 4number of teeth so positioned as to insure the successive closing and opening of each pair of switches in the manner hereinbefore described. In the normal condition of the apparatus, the teeth of cams and 65 respectively hold the switches 5 and 15 closed as shown.

The teeth of the ratchet wheel 76 are engaged by a pair of actuating pawls 80 and 81 pivoted toa suitable rocking frame 82 at 83 and 84 respectively. A spring 85 interconnects pawls 80 and 81 and holds them against the teeth of the ratchet wheel. Roclv'ing frame S2 is pivoted at S6 to a lever 87 and at 90 to an armature level' 91. Armature lever 91 is operated in one direction by the attractive force of an electromagnet 92 and in the other direction hy a retractile spring 93. A pair ot' stops 95 and 96 coperate with pro jcrtions 97 and 98, which extend from the pawls S`and 81, to limit the extent of cach step and to positively hold the cam shaft 70 in position between eath step.

The winding of electromagnet 02 is connected to a grounded source of-cnergy 93 and to a front contact 10G of relay 21 and a front contact lOl of relay 102. The wind ings of relays 21 and 102 are connected in multiple directly to the fixed contact 49 ot' line switch 40 and through a resistance 105 to the main line L and movable contact- 48 ofy line switch 40. The otherterminals of the windings of relays 21 and 102 are connected to ground and to their armatures 107 and 108 respectively. Armature 100 of rclaY 21 is connected to a grounded source of energy 110. Relays 21 and 102 are polarized. in the specific embodiment shown. relay 21 being responsive only to positive cm'rents while relay 102 is responsive to negative currents only. Resistance 105 is preferably so proportioned that its resistance plus the resistance of the parallel. path to ground through the windingv ot' relays 21 and 102 is equal Vto the resistance of line L and the apparatus connected therein at the distant station.

The operation ot' the selecting mechanism when used as a comhined impulse transmitter and effect distribute-r is as follows: The

manipulation of the apparatus for controlhnO' the ole chancers :l5 to 30 inclusive 1n ha u .h i u addltion to selectively 'transferring certain ot' the movable parts ol" these members trom the right tol the lett-hand contact, likewise shifts ino-Vahle contact 4S of line switch 40 from xed contact i9 to fixed contact Assuming that pole changer 35 has heelr shit'ted, there is a flow of positive current from source 47 through pole changer 85 and switch 15, contacts l5 and -l-S of line switch 46, and in parallel through line L and the resistance 105 and the windings of relays 21 one of the contact springs of switches o and 15. whereupon the switches are opened.. breaking' the previously traced circuits including pole changer 35 and winding; 25. The opening ot switch 15 terminates the First impulse over line il and through relays 2l and 102. causing the previously energized relay 21 to r ,lease its armatures 107 and 10S?. The release of armature 109 opens the circuit from battery 110 to its sel o'll switches,

while the release ol' armature 107 breaks the circuit for clert'omagnet 02.', The'deuergiation ot' electr-i)magnet .02 allows s'iring Sill to return armature lever lli, causing pawl S0 to engage a tooth of ratchet wheel 7G, giving the cam shaft a second step. This step causes the teeth '75 of cams 56 and 00 to close switches (i and 16. The closing ot switch 16 initiates the second impulse from battery l? through pole changer 3G to. line L and the polarized relaysl 2l and 102, while the etosingr of switch (i partially prepares a circuit for the winding 20 which will he completed through battery 110. provided this Second inipulse is ot' positive polarity to cause the enern gization ol relay 21. lt, however, the position of pole changer :l0 has not heen altered from its right-hand to its left-hand contact, a nega` tive impulse will he transmitted to line il) and the polarized relays 21 a nd 102. causing the encrgization of negatively polarized re lay 102. This condition merely causes the shaft 70 to take two steps, one upon the en- -ergization of elcctromagnet 02 and the other upon the denergization of this magnet. The denergiza'tion o't' the magnet marks the beginning oi the third impulse which is controlled hy pole changer 37. The third energization of the electromagnet 92 terminates the third impulse, and the third deinergization initiates the fourth impulse. controlled hy pole changer 38T' Theft'ourth de encrgization of the electromagnet completes the c vcle of operation and switches 5 and are again closed for the beginning of the next selection. Where the pole changers 35 to 39 inclusive are moved so as to connect the positive pole ot' source 47 to the line l2- and the polariffedrelays 21 and 102, the correspondingl windings 25 to 29 inclusive are energized in addition to the movement of the cani shaft 70, While if the pole changers are not so moved, the cani shaft 70 is :nado to execute its step-by-step movement Without the. energization of the corresponding mag 'nets 25 to 29 nclusive.

When the selecting mechanism is acting solely as a distributor ot'l the effects of our rent impulses'arriving from a distant station over lineli, the operation is precisely as #hereinabove described, eiieept that the iolarized relays 21 and 102 operated hy a seque-nee of current impulses flowing over line L instead of curreiit. from source 47, and the condition of line switch 46 remains un- 'lOO altered with movable Contact 48 in engagement with fixed Contact 49.

lVhat is claimed is: ,A

l. A selecting mechanism comprlsin'g a plurality of' switches, cams for actuating said switches-an electromagnet, and stepby-step apparatus vcooperating therewith and controlled by the cam-actuated switches for clfecting the rotation of said cams.

'2. A selecting mechanism comprising a plurality of sets of switches, current-polarity controlling means cooperating with one of said sets of switches, an electromechanism coperating with another of 'said sets of switches, mechanism for simultaneously actuating switches from both sets, and an electromagnet controlled by the first of said sets -of switches for operating said mechanism.

3. A selecting mechanism adapted for use as a current impulse transmitter and receiver comprising a plurality of sets of switches, impulse controlling circuit connections coperat-ing with said switches of'one of the sets,'electromechanism coperating with said switches of another of the sets, a device for simultaneously operating a plurality of said switches, there being at least one switch from at least two sets and an electromagnet for operating said device.

4. A selecting mechanism for producing a succession of current impulses comprising a source of current, a plurality of switches cooperating therewith and adapted to be operated in succession, a plurality of cams for actuating said switches, an electromagnet and step-by-step apparatus cooperating therewith for rotating said cams a plurality lplurality of sets of l selectively performing a of steps to actuate said switches successively, and current controlling means cooperating with 'said switches and said source to vary the effect of the cooperation of said switches and said cams.

5. A selecting mechanism comprising a switches, current con trolling means coperating with one of the sets to form a succession of current impulses, a selecting device cooperating With another 'of the sets to selectively control the performance of a plurality of functions, means for simultaneously closing switches of both sets, and an electromagnet for insuringthe step-by-step operation of said switch closing means.

6. A selecting mechanism for producing a selective succession of current impulses and plurality of functions comprising in combination a current controllingmeans for determining the character of the impulses produced, selecting devices for controlling the function performed, a `plurality of sets of switches, one set cooperating with said means and another with vsaid devices,^a switch actuator for closing both sets of switches, and an electromagnet for giving said actuator a step-by-step movement to invariably close said switches in the s: me order.

In Witness whereof, l hereunto subscribe my name this 24th day of February A. D.,

1915. FRED R. MCMURRY.

Witnesses:

E. "EDLER, K. L. STAHL. 

